The project aims are to advance the understanding of extrinsic regulations that apply to neural cells during development and adult life. Specifically, we intend to continue the investigation of: 1) use of serum-free defined media for neuronal cultures, 2) identification of serum constituents needed by glial cells for maintenance and growth, 3) the mechanism of action of Nerve Growth Factor on spinal sensory ganglionic neurons, and 4) survival, neurite production and metabolic behaviors of cultured ciliary ganglionic neurons.